Messages in this thread | | | Date | Tue, 16 Nov 2004 16:33:10 -0800 | From | Andrew Morton <> | Subject | Re: 21 million inodes is causing severe pauses. |
| |
Robin Holt <holt@sgi.com> wrote: > > On Tue, Nov 16, 2004 at 11:13:21AM -0800, Andrew Morton wrote: > > Robin Holt <holt@sgi.com> wrote: > > > > > > I guess I am very concerned at this point. If I can do a > > > release/reacquire, why not just change generic_shutdown_super() so the > > > lock_kernel() does not happen until the first pass has occurred. ie: > > > > > > --- super.c.orig 2004-11-16 10:22:17 -06:00 > > > +++ super.c 2004-11-16 10:22:41 -06:00 > > > @@ -232,10 +232,10 @@ > > > dput(root); > > > fsync_super(sb); > > > lock_super(sb); > > > - lock_kernel(); > > > sb->s_flags &= ~MS_ACTIVE; > > > /* bad name - it should be evict_inodes() */ > > > invalidate_inodes(sb); > > > + lock_kernel(); > > > > > > if (sop->write_super && sb->s_dirt) > > > sop->write_super(sb); > > > > > > This at least makes the lock_kernel time much smaller than it is right > > > now. It also does not affect any callers that may really need the BKL. > > > > lock_kernel() is also taken way up in do_umount(), hence the need for > > release_kernel_lock()/reacquire_kernel_lock(). > > It looks like it is only held very briefly during the early parts of do_umount. >
OK.
> I have moved lock_kernel() as above in addition to the two patches you pointed > to earlier. This has left me with a system which has 21M inodes and undetectable > delays during heavy mount/umount activity. I am starting one last test which > attempts a umount of a filesystem which has many inodes associated with it.
That sounds good. We need to work out where that null-pointer deref is coming from.
> At this point, I have checked the entire code path and see no reason the > BKL is held for the first call to invalidate_inodes.
No, the above change looks fine. And I have no problem merging up invalidate_inodes-speedup.patch, really - it's been in -mm for over a year. I've just been waiting for a decent reason to merge it.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |